Pulse regenerator



Jan. 13, 1942. K. D. SWARTZEL, JR

PULSE REGENERATOR Filed Sept. 28, 1940 INVENTOR A. D. SWARTZEL, JR.

ATTORNE) Patented Jan. 13, 1942 UNiTED STATES PATENT OFFICE PULSEREGENERATOR Karl D. Swartzel, Jr., Teancck, N. J., assignor to BellTelephone Laboratories, Incorporated, N ew York, N. Y., a corporation ofNew York Application September 28, 1940, Serial No. 358,811

7 Claims.

This invention relates to signaling systems and particularly to impulseregenerating means used in telephone systems.

The object of the invention is to provide simple and economical meansresponsive to dialed subscriber line impulses for sending out similartrains of impulses regenerated by means which will assure the properstrength, length and timing thereof regardless of any mutilation of theincoming impulses. Means of this nature may be used at an intermediatepoint in a long line where the incoming impulses may not be seriouslymutilated but would be if they traversed the entire length of the line,and where simple relay repeating means would be inadequate since suchmeans have no correcting action but would tend to aggregate anymutilation.

In accordance with this invention a plurality of number discs areprovided, one for. each digital train of impulses to be repeated. Theincoming impulses of a train will rotate a disc as many steps 01f normalas there are impulses in the train. Later this disc will be returned tonormal and during this return movement outgoing impulses of properstrength, length and timing will be transmitted, the number beinggoverned by'the distance the disc had been rotated oif normal.

' A feature of the invention is a splined shaft which may be given astep-by-step longitudinal movement whereby it will be moved intoengagement with a separate disc on each step. While in engagement witheach separatedisc this shaft may be given a step-by-step rotary'movementto rotate that disc with which it is engaged. Thus the said discs may beeach rotated selectively so that when all the discs have been so set acomplete telephone designation will be recorded.

Another feature of the invention is a splined shaft which may be movedin like manner but rotated in the opposite direction, in combinationwith means for automatically stopping the rotary movement when a discreaches its normal position and for then giving the shaft a singlelongitudinal step to bring it into engagement with the next disc.

In accordance with another feature of the invention the first orrecording shaft retreats step by step from the first to the last discand the second or transmitting shaft advances step by step from thefirst to the last disc.

' Another feature is a releasing means whereby after the first orrecording shaft has retreated to its ultimate position and the second ortransmitting shaft has followed and advanced to its ultimate position,whereupon the device has completed its function, both shafts willsimultaneously and automatically be returned to normal.

A further feature is a train of slow-operating relays which control theaction of the transmitting shaft to govern its speed so that thetransmitted impulses and the 'i'nterdi-git pause between trains ofimpulses will be properly timed.

The drawing consists of a single sheet containing two figures.

Fig. 1 is partly in the form of a circuit dia gram and partly in theform of a schematic perspective drawing of the mechanical arrange ments;and

Fig. 2 is an exploded view of the n'umb-e'rdiscs and the cooperatingshafts, showingschemathcally the relation between the shafts and'thenumber discs.

The invention is illustrated as being included in a telephone system.Here a subscriber at substation l is establishing a connection to asubscriber at substation 29. The subscriber at substation I removes hisreceiver and in the usual manner a line finder 3 or other automaticswitching arrangements extend his line to the apparatus illustrated inthe body of this drawing. A circuit is then established from ground overthe line and through the substation dial 2 and the circuit of substation.l, the winding of relay ,4 to battery. Relay 4 attracts its armaturesand closes a circuit through the winding of the rotary stepping magnet30 to cause the energization of this magnet. -At the same time a circuitis J closed from battery 3| through the winding of slow-releasing relay5, the front contact and upper armature of relay 4 to battery 3|,whereby relay 5 becomes operated. When the subscriber at substation Idials, the train of impulses consists of a plurality of breaks in theline circuit.

- Upon the first of these breaks, the armatures of relay 4 return totheir normal position whereupon a circuit is established from battery 3!through the armature and front contact of slowreleasing relay 5, thewinding of slow-releasing relay 6, the back contact and upper armatureof relay 4 to battery. The winding of relay 5 is opened but this beingslow to release does not return its armature to normal over th periodmeasured by the dialing impulse; Relay 6 thereupon establishes a circuitfrom battery 3| through the armature and front contact of relay 5, thefront contact and armature of relay 6, the winding of the steppingmagnet 32 and thence back to battery 3|. Magnet 32 attracts the armaturel preparatory to stepping the shaft 33 in a longitudinal direction tothe left.

Upon each break in the line the circuit of stepping magnet 30 is broken,whereupon the armature 1 under spring control returns to normal andthereby rotates the shaft 33 in a counterclockwise direction (whenfacing the mechanism from the right end).

A plurality of number discs like the right-hand disc 14 and theleft-hand disc 31 are mounted in any appropriate manner with a shaft 33extending through them but not in physical contact therewith. Each discis provided with a female formation cooperating with the splines l3 onthe right-hand end of the shaft 33 whereby the shaft may engage androtate the number discs separately. The number of discs provided willcorrespond to the number of digits to be registered.

The shaft 33 is provided at its extreme righthand end with a pluralityof splines l3 which are only long enough to engage a single disc I4.Therefore, as the magnet 30 operates, the disc [4 will be rotated in acounter-clockwise direction a number of steps equal to the number ofimpulses in this train of impulses.

It should be noted that the disc I4 is provided with a camming formation34 which causes the contact spring I5 to close a circuit to the contactspring 35 as the disc I4 is stepped off normal. Similarly, as the discI4 is returned to its normal position as will be hereinafter described,a circuit is established between the contact spring and the contactspring 35. On the forward movement, that is the movement caused by thecounter-clockwise rotation of the shaft 33, the closing of this contactwill be ineffective but upon the return movement this contact willbecome effective.

It should also be noted that the disc I4 is cut in such a way that thespring I 5 will drop into a serration at the end of each step toproperly center the disc and hold it in position.

After the proper number of steps of the shaft 33 has been taken undercontrol of the dial 2 there will be a pause, spoken of as the interdigitpause, during which the relay 4 will hold its armatures attracted for aperiod of time long enough to allow the relay 6 to become deenergize'd.Upon this action, the magnet 32 will become deenergized and the armatureill under spring control will cause a longitudinal movement of the shaft33 whereby the splined end l3 will now come into engagement with thesecond number disc 36. Thereafter, the subscriber at substation I willdial and cause the disc 36 to be rotated in a counter-clockwisedirection a number of steps equal to the digit dialed.

In this manner each of the eight number discs will be set and thereby atelephone number will be recorded on such discs.

Upon the setting of the last of these discs 31 another contactarrangement will be operated. This consists of a contact spring l1,normally resting on the camming surface 16, whereby a back contact 38 isclosed and a front contact 39 is opened. As the disc 31 is moved offnormal the contact spring I! will now transfer its contact from thespring 38 to the spring 39. During the first off-normal step a spring40, similar to the spring l5, will be operated whereby a momentarycontact is made to the spring 4|. At this time a circuit may be tracedfrom battery, the spring H, the spring 39, the spring 4|, the spring 40to the winding of a slow-releasing relay 25, to ground. At the end ofthis first step the momentary contact between the springs 40 and 4| willbe broken and therefore the circuit for relay 25 will be opened. Duringthe energization of relay 25 a circuit for the energization of steppingmagnet 42 will be closed through the lower armature and front contact ofrelay 25. After a period of time, equal to the proper interdigit pause,has expired, relay 25 will release its armatures whereupon the magnet 42will release its armature 26 and cause the shaft 43 to be given onelongitudinal step toward the left. This will bring the splined end ofthe shaft 43 into engagement with the first disc l4 and at the same timewill allow the off-normal spring 22 to move to the left to ground thetwo conductors 44 and 45. At the completion of this longitudinalmovement a circuit will be established from battery, the armature ofmagnet 42, the back contact and upper armature of relay 25, the windingof relay 26, the back contact and lower armature of relay 21, conductor44, to ground on the off-normal spring 22. Relay 26 becomes energized inthis circuit and a normally closed circuit for magnet 46 is therebyopened whereby the armature l8 releases and causes the shaft 43 to takeone step in a clockwise direction. At the same time relay 26 closes acircuit for the relay 2! through its inner upper armature and frontcontact, so that relay 2'! now becomes energized. Normally, a circuit isclosed from battery through the upper armature and back contact of relay2'! to the apparatus controlled by outgoing impulses and hererepresented by the switch contacts 28. When relay 26 becomes operatedthe upper armature and back contact of relay 2'! are bridged, so thatthe front contact and upper outer armature of relay 26 substitute forthe upper armature and back contact of relay 21. Relay 2'! opens thecircuit of relay 26 and, therefore, after an appropriate interval, relay26 releases its armatures, so that the circuit for magnet 46 is againestablished. During this period the circuit toward the switch 28 isopened and this constitutes a timed pulse transmitted by this apparatus.The proper timing is achieved by the proper construetion and adjustmentof the two slow-releasing relays 26 and 21. After relay 26 has beenrestored for a sufficient time then relay 2! releases, whereupon thecircuit for relay 26 is again established and the magnet 46 allows thearmature l8 to rotate the shaft 43 another step in a clockwisedirection.

In this manner the disc 14 is returned, step by step, to its normalposition and a corresponding number of impulses are transmitted towardthe switch 28. As the disc I4 reaches its normal position the spring l5rides up over the camming surface 34, so that a connection is nowestablished from battery contact l1, contact 39, contact 35, contact l5,winding of relay to ground. Relay 25 operates and causes theenergization of magnet 42 which, moving its armature 26, prepares tostep the shaft 43 from engagement with the disc M to engagement with thedisc 36. At the same time the battery connection to the armature 20 andthence to the back contact and upper armature of relay 25 is broken, sothat relay 26 is deenergized for the interdigit pause caused by theproper timing adjustment of slow-release relay 25. At the end of thistiming period the connection between contacts l5 and now being open,relay 25 releases, causing the shaft 43 to be stepped into engagementwith disc 35, ready to initiate the clockwise movement of the disc 36.

In this manner each of the number discs in turn is rotated back tonormal and properly timed trains of impulses are transmitted to theswitch 28 representing a train of automatic switches.

As the last disc 31 returns to normal a connection is established fromground, off-normal contact 22, conductor 45, the two release magnets 4'!and 48 in parallel, spring 38, spring I! to battery. These releasemagnets become energized and attracting their armatures l2 and 2!release the shafts 33 and 43, respectively, which thereupon return tonormal in the usual manner employed in the working of such two-movementstep-by-step mechanisms. Upon the full return to normal of the shaft 43the off-normal spring 22 opens the ground connection to the conductors44 and 45 and the apparatus is now in its normal position awaiting usein some other connection.

What is claimed is:

1. A pulse repeater for repeating a plurality of trains of pulsescomprising a like plurality of rotatable members mounted on a commoncenter line, a shaft mounted on said common center line provided withmeans for rotating each said member separately, means responsive totrains of pulses for successively moving said shaft into engagement withsaid members, means responsive to the pulses of said trains of pulsesfor rotating said members, a second shaft mounted on said common centerline provided with means for rotating each said member separately,automatic means for successively moving said second shaft intoengagement with each of said members and for rotating each of saidmembers a distance corresponding to the distance each had been rotatedby said first shaft, and means controlled by said last-named means fortransmitting pulses.

2. A pulse repeater for repeating a plurality of trains of pulsescomprising a like plurality of rotatable members mounted on a commoncenter line, a shaft mounted on said common center line provided withmeans for rotating each said member separately in one direction, meansresponsive to trains of pulses for successively moving said shaft intoengagement with said members, means responsive to the pulses of saidtrains of pulses for rotating said members, a second shaft mounted onsaid common center line provided with means for rotating each saidmember separately in the opposite direction, automatic means forsuccessively moving said second shaft into engagement with each of saidmembers and for rotating each of said members a distance correspondingto the distance each had been rotated by said first shaft, and meanscontrolled by said last-named means for transmitting pulses.

3. A pulse repeater for repeating a plurality of trains of pulsescomprising a like plurality of rotatable members mounted on a commoncenter line, a shaft mounted on said common center line provided withmeans for rotating each said member separately in one direction, meansresponsive to trains of pulses for successively moving said shaft intoengagement with said members, means responsive to the pulses of saidtrains of pulses for rotating said members from a normal position, asecond .shaft mounted on said common center line provided with means forrotating each said member separately in the opposite direction, meansfor successively moving said secand shaft into engagement with each ofsaid members, means for rotating each of said-mom bers back to normal,contact means operated by each of said members as said members reachnormal position for controlling said movements of said second shaft, andmeans controlled by said means for moving said second shaft for transmitting pulses.

4. A pulse repeater or repeating a plurality of trains of pulsescomprising a like pluralityof rotatable members mounted on a commoncenter line, a shaft mounted on said common center line provided withmeans for rotating each said member separately in one direction, meansresponsive to trains of pulses for successively moving said shaft intoengagement with said members, means responsive to the pulses of saidtrains of pulses for rotating said members from a. normal position, asecond shaft mounted on said common center line provided with means forrotating each said member separately in the opposite direction, meansfor successively moving said second shaft into engagement with each ofsaid members, means for rotating each of said members back to normal,contact means operated by each of said members as said members reachnormal position for controlling said movements of said second shaft,means responsive to the return to normal of the last of said members tobe set by said first shaft for automatically returning both of saidshafts to normal, and means controlledby said means for moving saidsecond shaft for transmitting pulses.

5. A pulse repeater for repeating a plurality of trains of pulsescomprising a like plurality of rotatable members mounted on a commoncenter line, a shaft mounted on said common center line provided withmeans for rotating each said member separately in one direction, meansresponsive to trains of pulses for successively moving said shaft intoengagement with said members, means responsive to the pulses of saidtrains of pulses for rotating said members from a normal position, asecond shaft mounted on said common center line provided with means forrotating each said member separately in the opposite direction, meansfor successively moving said second shaft into engagement with each ofsaid members, means for rotating each of said members back to normal,contact means operated by each of said members as said members reachnormal position for controlling said movements of said second shaft,contact means operated by the movement of said second shaft off normal,means including said last means and said contact means operated by thelast of said members for returning both said shafts to normal upon thearrival of the last of said members at its normal position, and meanscontrolled by the said means for moving said second shaft fortransmitting pulses.

6. A pulse repeater for repeating a plurality of trains of pulsescomprising a like plurality of rotatable members mounted on a commoncenter line, a shaft mounted on said common center line provided withmeans for rotating each of said members separately in one direction,means responsive to trains of pulses for successively moving said shaftinto engagement with said members, means responsive to the pulses ofsaid trains of pulses for rotating said members from a normal position,a second shaft mounted on said common center line provided with meansfor rotating each said member separately in the opposite direction,means for successively moving said second shaft into engagement witheach of said members, means for rotating each of said members back tonormal, a train of slop-operating relays for controlling the means formoving said second shaft in both its longitudinal and its rotarydirections, said relays being adjusted and arranged to operate in timeintervals to properly time the length of outgoing pulses and theinterdigit pause between trains of pulses, and means controlled by saidrelays for transmitting outgoing pulses.

7. A pulse repeater for repeating a plurality of trains of pulsescomprising a like plurality of rotatable members mounted on a commoncenter line and each having a grooved internal cylindrical formationcoaxial with said common center line, a shaft mounted on said commoncenter line provided with splines longenough only to engage one of saidmembers at a time, means responsive to trains of pulses for successivelymoving said shaft into engagement with said members, means responsive tothe pulses of said trains of pulses for rotating said members in onedirection, a second shaft provided with like splines mounted on saidcommon center line, automatic means for successively moving said secondshaft into engagement with each of said members and for rotating each ofsaid members in the opposite direction a distance corresponding to thedistance each had been rotated by said first shaft, and means controlledby said last means for transmitting pulses.

KARL D. SWARTZEL, JR.

